/*
 *  Copyright 2008 Danny Lagrouw
 *  
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *  
 *      http://www.apache.org/licenses/LICENSE-2.0
 *  
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License. 
 */
package org.bastion.adapter;

import org.bastion.exception.InvalidQueryServiceException;
import org.bastion.exception.UnsupportedQueryException;
import org.bastion.message.QueryMessage;
import org.bastion.query.IDomainQuery;
import org.bastion.service.QueryService;

@SuppressWarnings("unchecked")
public class QueryAdapter implements Adapter<QueryMessage> {

	private final QueryService service;

	public QueryAdapter(QueryService service) {
		this.service = service;
	}
	
	@Override
	public void handle(QueryMessage message) {
		IDomainQuery query = message.getQuery();
		if (service.prefersNamedQueries()) {
			if (query.getName() != null) {
				message.setResultList(service.executeQuery(query.getDomainClass(), query.getName(), query.getParameters()));
			} else if (!query.hasMatcher()) {
				message.setResultList(service.executeQuery(query.getDomainClass()));				
			} else if (service.supportsPredicateQueries()) {
				message.setResultList(service.executeQuery(query.getDomainClass(), query.getMatcher()));							
			} else {
				throw new UnsupportedQueryException(service, query);
			}
		} else if (service.prefersPredicateQueries()) {
			if (query.hasMatcher()) {
				message.setResultList(service.executeQuery(query.getDomainClass(), query.getMatcher()));
			} else if (query.getName() == null) {
				message.setResultList(service.executeQuery(query.getDomainClass()));				
			} else if (service.supportsNamedQueries()) {
				message.setResultList(service.executeQuery(query.getDomainClass(), query.getName(), query.getParameters()));				
			} else {				
				throw new UnsupportedQueryException(service, query);
			}
		} else {
			throw new InvalidQueryServiceException(service);
		}
	}

}
